Molded block stripping mechanism



April 19, 1960 T. K. ZEVELY 2,932,876

MOLDED BLOCK STRIPPING MECHANISM Filed July 11, 1956 3 Sheets-Sheet 1 3 INVENTOR THOMAS K ZEVELY 0 BY L W,

ATTORNEYS April 19, 1960 T. K. ZEVELY MOLDED BLOCK STRIPPING MECHANISM 3 Sheets-Sheet :2

Filed July 11, 1956 FIGB n 3 2 H 0 J H T 9 K9 H n J m u u 3 L a 4 J n P n W g H m w w n M a H R 4 h M a u j j n W L m M W m a [Iv W Ll FII'II: IIIIIIII H T k I J u H u 9 9 u IN VENTOR TH O M AS K Z E V E LY Gannuwn, W

ATTORNEYS April 19, 1960 T. K. ZEVELY MOLDED BLOCK STRIPPING MECHANISM 3 Sheets-Sheet 3 Filed July 11, 1956 FIG.4

FIG.5

INVENTOR THOMAS K ZEVELY ATTORNEYS surfaces of the blocks.

United States MOLDED BLOCK STRIPPING MECHANISM Thomas K. Zeveiy, Washington, D.C., assignor to The Washington Brick C0,, Muir-kirk, Md, a corporation of Maryland Application July 11, 1956, Serial No. 597,149 6 Claims. (31. is -4i This invention relates to block molding machines of the type adapted to automatically produce cored or hollow building blocks of cinder, slag, concrete or similar materials, and is directed primarily to an improved mechanism forstripping such blocks from the compartmented molds in which they are formed.

In block molding machines of the type wherein the mold cores are supported by core bars extending across the top of the mold box and the finished blocks are ejected by either raising the mold box relatively to the blocksupporting pallet or lowering the pallet relatively to the mold box, it is customary to engage the tops of the blocks with stripper heads to facilitate the stripping operation and at the same time smooth and compact the upper surfaces of the blocks. in the interest of simplicity, the following description will refer to machines of the type wherein the mold box remains stationary and the stripping mechanism and block-supporting pallets move vertically during the stripping operation. However, it will be understood that the invention is equally adaptable to machines wherein the mold box in the movable element and the stripping mechanism, as a whole, remains stationary.

.Due to the presence of the core bars, a plurality of stripper heads must be. provided for each block, the heads being spaced apart sufficiently to receive the core bars rherebetween as the heads move downwardly to engage the tops of the blocks and strip them from the mold. When the stripper heads are rigidly fixed at their upper ends to the plate by which they are supported and given their vertical movement, the stripper shoes at the lower ends of the heads are always separated by spaces slightly greater than the width of the core bars. The result is that, in such a construction, the moldable blockforming material or aggregate lying directly beneath the core bars is not engaged by the stripper shoes and compressed or packed thereby to the same extent'as the rest of the upper faces of the blocks, and when the blocks are cured, cracks or weakened areas frequently develop at these points. Even when the cracks or faults do not develop sufiiciently to seriously impair the strength of the blocks, the failure of the stripper shoes to engage those portions of the blocks lying beneath the core bars leaves noticeable irregularities in the otherwise smooth These defects are particularly serious in the case of large blocks having relatively thin walls, and are magnified when the blocks are made of slag and similar materials which are not as free-flowing or plastic as cinder and like aggregates.

Rigidly supported stripper heads also produce excessive wear of the mold liners and compartmenting division plates, because any vertical misalignment of the stripper heads and the elements of the mold box results in undesirable frictional contact therebetween as the stripper heads move up and down; and since the greatest wear occurs at the top of the mold where the stripper heads first come in to contact therewith, the upper portions of the blocks become larger as the wear increases, thereby making the stripping operation more diiiicult.

In my Patent No. 2,566,787, dated September 4, 1951, there was disclosed a novel stripping mechanism for automatic block molding machines of the general character above described which is capable of effectively leveling and compacting the material of the blocks uniformly over the entire area of their upper faces so as to leave no weak points or observable surface irregularities therein which would impair either the strength or the appearance of the blocks. The mechanism of said patent was characterized by the inclusion of pivotally supported stripper heads and means for automatically opening and closing the gaps between the stripper shoes as the heads move upwardly and downwardly relative to the mold so as to enable the shoes to pass around the core'bars, but'to come together thcrebeneath and engage the entire upper surfaces of the blocks in the mold during the stripping operation.

I have also disclosed in my application Serial No. 451,477, filed August 23, 1954, now Patent No. 2,887,- 755, an improved stripping mechanism for obtaining substantially the same results as those produced by the patent d structure, but which is simpler in construction, less expensive to manufacture, more positive and reliable in operation, and less expensive to maintain than the mechmanufacture of elongated blocks having three or more linearly disposed cored openings per block, such as the soffit blocks commonly used as floor filler units.

inasmuch as blocks of this character require the use of at least three cores in transverse alignment in the mold hox without the interposition of division plates on which cam members might be mounted as disclosed in my earlier application, another object is to provide a novel stripping mechanism wherein the stripper shoes, which are maintained in separated positions at all times other than when they are in contact with the blockforrning material in the mold box, are moved into closed positions beneath the core bars some by contact with inclined cam surfaces at the ends of the mold box and some as a result of the movement of adjacent stripper shoes.

These and other objects will appear more fully upon consideration of the detailed description of the invention which follows. In this connection, although only one specific embodiment of the inventive concept is described and illustrated in the accompanying drawings, it is to be expressly understood'that these drawings are illustrative only and are not to be construed as representing the full scope of the invention as it is defined in the appended claims.

Referring now to the drawings, wherein like reference characters indicate like parts throughout the several views:

Fig. 1 is a front view of one form of stripping mechanism and mold box embodying the present invention adapted for use in a well-known type or" automatic block molding machine, certain parts having been broken away or entirely omitted, and other parts being shown in section, in order to clearly illustrate the essential characteristics of the structure;

Fig. 2 is a plan view of the mold box of Fig. 1, showing a core and core bar arrangement adapted to produce two elongated hollow blocks each having four aligned cavities;

Fig. 3 is a fragmentary front view, partially in section, of the stripper heads and mold box of Fig. 1 showing the elements in the positions occupied when the stripper shoes are in closed positions beneath the core bars, in contact with the tops of the blocks;

Fig. 4 is a plan view of the stripping mechanism of Fig. 1, omitting the fore-and-aft bars and transversely extending beams from which the mechanism is normally suspended; and

Fig. 5 is a side view of the upper end of the mechanism of Figs. 1 and 4, partially broken away and partially in section substantially on line 55 in Fig. 4.

Referring first to Figs. 1 and 2, the stripping mechanism and mold illustrated therein are, except for the improvements constituting the present invention, similar to the corresponding elements shown in my previously mentioned Patent No. 2,566,787 and application Serial No. 451,477, and are adapted for use in the well-known Besser type of automatic block molding machine wherein hollow or cored blocks are made on plain or imperforate pallets. In such a machine, the blocks are formed in a mold 11 which is stationary except for the movements incident to vibration of the mold during the block forming operations, the moldable material being supplied to the mold box through the open top thereof by a horizontally'reciprocable feed pan (not shown). During the molding operation, the open bottom of mold box 11 is closed by an imperforate pallet 12, the pallets being fed automatically from a pallet stack to a position below the mold box and then elevated into engagement with the bottom of the mold by vertically reciprocable anvil bars '13." When the pallet engages with the bottom of the mold, the mold box is elevated slightly so that the transversely extending mold bars 14 which support the mold are out of contact with the portions of the machine framework on which they normally rest. The mold box is then ready to receive the charge of moldable material from the feed pan which moves forwardly over the mold box and delivers the charge by gravity through the open bottom of the pan. During delivery of the charge, the

mold box and superposed feed pan are vibrated in known manner.

When the mold has been filled, the feed pan is moved rearwardly clear of the mold box so as to enable the stripping mechanism '15, which is normally maintained in an elevated position as indicated in Fig. l, to descend into contact with the upper surface of the material in the mold to first level and compact said material, during which time the mold box is again vibrated and the stripper heads 16, 17, 1 8, 19, 20 are permitted to gradually sink by gravity as the material is compacted, and to then ,move downwardly through the mold box and positively (not shown) which advance the loaded pallet to an uu loading position, whence the pallet andblocks may be removed from the machine, either manually or automatically, and transported to the curing vault. Asthe loaded pallet is moved to the unloading position after the stripping operation, the pallet chains automatically bring another empty pallet into position beneath the mold box, and the anvil bars are again elevated to lift the empty pallet into engagement with the bottom of the mold. Simultaneously with the upward movement of the anvil bars, the stripping mechanism 15 is moved upwardly out of the mold box and returned to its initial position illustrated in Fig. 1. The vertical movements of the stripping 4 mechanism and anvil bars, and the cooperative horizontal movements of the feed pan, are controlled in known manner by cams.

The stripper heads 16, 17, 18, 19, 20 are supported at their upper ends in a manner hereinafter described by a horizontal plate 26 which is in turn secured to a pair of fore-and-aft bars 27 by bolts 28. The bars 27 are fixed in any suitable manner, as by welding, to the lower edges of a pair of parallel beams 29 which extend transversely from one side of the machine to the other and are connected at their ends to a suitable cam and lever system, such as that shown in my Patent No. 2,566,787, by which the stripping mechanism is given its vertical movements in timed relation to the movements of the feed pan and anvil bars.

In the structure shown in Figs. 1 and 2, the mold 11 comprises front and rear side liners 30, 31 and end liners 32, 33 which form the walls of the mold box and are secured to mold bars 14 in any suitable manner, as by bolts (not shown). The interior of the mold box may be divided into two or more block forming compartments by means of one or more transversely extending division plates 34 bolted to end liners 32 and 33 in known manner. A tray 35, having its bottom flush with the upper surfaces of mold liners 30, 31 and division plate 34 and a vertical rim around all but the rear side thereof, surrounds the upper end of the mold box and is supported on the upper edges of mold bars 14.

In order to form cavities of the desired number and shape in the blocks molded in mold 11, the mold box is provided with a plurality of mold cores 36, 37, 38, 39

which are fixed to and suspended from the lower edges of core bars 40, 41, 42, 43, respectively. The core bars extend across the top of the mold box in fore-and-aft directions and are fixed thereto in proper position by means well known to-the art. Except for those portions which rest on the upper surfaces of front and rear side liners 30, 31 and the portions to which the cores are connected, the lower edges of the core bars overlying the interior of the mold box are positioned Well above the upper surfaces of the mold liners and division plate, and also above the normal level of the moldable material in the mold box prior to compaction. For a purpose which will appear hereinafter, the two outer core bars 40, 43 which are closest to the ends of the mold box are preferably so constructed or supported that their lower edges lie in a horizontal plane above that of the lower edges of the two inner core bars 41, 42. The lower edge of each core bar is preferably beveled on the side furthest from the fore-and-aft center line of the mold as indicated at 44, also for a purpose later to be described.

With the elements of mold 11 arranged as illustrated in Fig. 2 so as to simultaneously produce two quadruple cavity'bl'ocks on a single pallet, the blocks being arranged with their longer dimensions parallel to the front of the machine and the core bars extending in'fore-and -aft directions; the stripper heads of stripping mechamsm 15 are so constructed as to provide, for each block forming compartment of the mold, a central fixed head 18, a first 17, 19 located adjacent to and on opposite sides of the fixed head, and a second pair of movable heads 16, 20 located adjacent to and outwardly of movable heads 17, 19, respectively. Although two groups of separately formed, individually supported stripper heads may be provided, one group for each block forming compartment, the illustrated embodiment of the invention comprises five twin heads each of which is symmetrical with respect to the vertical plane of transverse division plate 34, somewhat similar to the construction shown in Figs. 12-14 of my Patent No. 2,566,787.

As indicated in Figs. 1 and 5, each of the outer pair of movable heads 16, 20 comprises a vertically extending side wall 45, front and rear end'walls 46, 47 and a pair of interior walls 48, 49, all welded together to form an assass n integral body. Detachably connected to the lower end of the thus formed stripper head body is a pair of stripper shoes 21 (head 16) or 25 (head each of which shoes is substantially C-shaped in plan, as shown in broken lines in Fig. 4, and is adapted to contact the end portion of the upper surface of one of the blocks formed in the mold. The adjacent transversely extending arms of the shoes of each pair are spaced apart, as indicated in Fig. 5, by a distance approximately equal to the width of transverse division plate 34, while the side wall 45 of the stripper head is cut out as indicated at 50 so as to receive the divisions plate as the stripping mechanism moves downwardly during the stripping operation.

The free or inboard ends of the arms of each stripper shoe 21, extend inwardly beyond the edges of the associated front and rear end walls 46, 47 of the stripper head body and are beveled as indicated at 51 at a some-' what greater angle relative to the vertical than the beveled portions 44 of core bars 40, 43. This construction enables stripper shoes 21, 25 to slide under core bars 40, 43, in contact with the beveled portions thereof, just as soon as the shoes clear the lower edges of said bars during downward movement of the stripping mechanism and to then move inwardly beyond the unbeveled sides of the core bars so as to engage and push stripper shoes 22, 24 of the inner pair of movable heads 17, 19 toward and into abutment with the shoes 23of fixed head 18.

Each of movable stripper heads 16, 20 is pivotally suspended on a bolt or spindle 52 from a mounting plate 53 which is detachably secured to supporting plate 26 by bolts 54 and nuts 55. Each spindle 52 has a horizontal axis parallel to the core core bars and is supported in two pairs of bearing brackets 56 which are welded to and extend downwardly from the lower surface of mounting plate 53, two of said brackets being located adjacent the ends of spindle 52 while the other two provide support for the central portion of said spindle. A pair of flexible rubber bushings 57 surround those portions of spindle 52 which extend between the outer and inner bearing brackets 56 so as to provide a torsionally resilient mounting for the spindle in said brackets. Wear take-up spacers 94 of slightly less diameter than the bores of bearing brackets 56 are interposed between the head and nut of spindle 52 and the outer ends of rubber bushings 57 so that, by tightening the spindle nut, any looseness g in the spindle mounting may be eliminated. A spacer 58 is also provided around spindle 52 between the two inner bearing brackets to prevent bushings 57 from moving axially toward one another when the spindle nut is tightened. Each stripper head 16, 20 is connected to its supporting spindle 52 by a pair of upwardly projecting hanger members 59 which are mounted on the portions of bushings 57 intermediate the two pairs of brackets 56. Hanger members 59 are fixed in any suitable mannor, as by Welding, heads 16, 2G.

The inner pair of movable stripper heads 17, 19 are of generally the same construction as the outer pair of heads 16, 26 and are pivotally suspended from mounting plate'53 in similar manner by means of spindles 60, bearing brackets 61, bushings '62 and hanger members 63. The body structure of stripper heads 17, 19 difiers slightly from thatof heads 16, 20 in that the transversely extending walls of each head 17, 19 corresponding to end walls 46, 47 and interior walls 48, 49 of heads 16, 20 are welded to a pair of fore-and-aft supporting walls 64 which are substantially coplanar with spindles 60, instead of to a single side wall like wall 45. The thus formed twin portions of each head are secured to hanger members 63 by welding the upper edges of walls 64 to the bottoms of said hanger members 63, and are tied together by a strap plate 65 which may be welded to the upper portions of the end and interior walls and to the edges of hanger members 63. The lower edges of strap plates 65 are positioned in substantially the same plane as the upper to the side walls of stripper ends of cut-outs in sidewalls 45 of movable heads 16, 20.

Detachably connected to the lower end of the body portion of each of stripper heads 17, 19 is a pair of stripper shoes 22 (head 17) or 24 (head 19) each of which shoes is approximately I-shaped in plan, as indicated in broken lines in Fig. 4 and is adapted to contact the portion of the upper surface of one of the blocks formed in mold 11 which lies intermediate the end and central portions engaged by the shoes 21 or 25 and 23, respectively. The outer ends of the cross arms of shoes 22, 24 are provided with vertical edges against which the beveled edges of shoes 21, 25 are adapted to abut,while the inner ends of said cross arms are beveled as indicated at 66 at substantially the same angle as the beveled portions 51 of shoes 21, 25 so as to enable shoes 22, 24 to come into abutment with shoes 23 of fixed stripper head 18 just as soon as the shoes clear the lower edges of core bars 37, 38 during downward movement of the stripping mechanism.

Fixed stripper head 18 consists essentially of a vertical plate 67pcoplanar with the fore-and-after center line of the mold which is fixed at its upper edge, as by welding, to the bottom of a mounting plate 68 which is in turn detachably secured to supporting plate 26 by bolts 6% and nuts 70. The lower end of vertical plate 67 carries a pair of removable stripper shoes 23 each of which, as indicated in broken lines in Fig. 4, is substantially I-shaped in plan and is adapted to contact the central portion of the upper surface of one of the blocks formed in mold 11. Each shoe 23 is detachably secured to plate 67 in any suitable manner with the portion corresponding to the central stem of the I-shape substantially co planar with plate 67 and the transversely extending arms projecting on opposite sides of said plate so as to cooperate with the inwardly extending beveled portions of shoes 22, 24 of the inner pair of movable stripper heads 17, 19. Inasmuch as stripper shoes 23 of the fixed stripper head have no lateral or horizontal movement relatively to the core bars, the edges of said shoes at the ends of the cross arms are vertical and the shoes are so dimensioned that said edges just clear the inner sides of core bars 41, 42 during vertical movement of the stripping mechanism. The adjacent arms of stripper shoes 23 are spaced apart by a distance approximately equal to the width of transverse division plate 34, while the central portion of plate 67 is cut out up to substantially the same level as the cut-outs 56 in the side walls 45 of movable heads 16, 20, so as to receive the transverse division plate during the stripping operation.

As indicated in Fig. l, as long as the stripping mechanism 15 is in an elevated position above and out of contact with the mold 11, movable stripper heads 16,

17, 19, 29 are maintained in inclined positions with the adjacent edges of the stripper shoes separated from one another and the lower ends of said heads oiiset horizontally from the core bars, out of alignment with the mold compartments into which they are adapted to enter. In the illustrated embodiment of the invention, springs are provided for normally maintaining the movable stripper heads in separated position, although it will be obvious that the same result could be obtained gravitationally by proper relative positioning of the pivotal axes and centers of gravity of the heads, as disclosed in my previously mentioned application Serial No. 451,477.

As shown in Figs. 1, 4 and 5, one of hanger members 59 of each of the outer pair of movable heads 16, 20 is provided with a rocker arm 71 which extends upwardly through aligned openings 72 and 73 in mounting plate 53 and supporting plate 26, respectively, and terminates in a head 74 one side of which is normally maintained in engagement with an adjustable stop 75 by a compression spring 76. Spring 76 is mounted in a recessed housing 77 fixed to the upper surface of supporting plate 26 and thrusts against a block 78 which extends forwardly from the head 74 of rocker arm 71 and is detachably connected thereto by a bolt 79. The thrust of springs 76 is such as to move stripper'heads 16, 20 about the axes of their spindles 60 in directions to separate stripper shoes 21, 25 from the adjacent vertical edges of shoes 22, 224 of the inner pair of movable stripper heads 17, 19. The pivotal movement of stripper heads 16, 20 in the shoe opening direction is limited by engagement of rocker arm heads 74 against stops 75 which, as indicated in Figs. 1 and 4, are cylindrical in form but are eccentrically mounted on bolts 80 threaded into blocks 81 fixed to supporting plate 26. By loosening bolts 80 and rotating stops 75 before retightening the bolts, the normal inclined positions of stripper heads 16, 2% may be adjusted.

' Movable heads 17, 19 are likewise provided with rocker arms 82 extending upwardly from their hanger members 63 through openings 83 and S4 in plates 53 and 26, respectively, the rocker arms 82 having heads 85 adapted to abut adjustable stops 86 and being fitted with forwardly extending blocks 87 and bolts 83 of substantially the same construction as the corresponding elements associated with movable heads 16, 2%. However, in lieu of compression springs thrusting against blocks 87, heads 17, 19 are yieldably urged into inclined positions by means of a tension spring 89 the ends of which are hooked into holes in a pair of laterally extending arms 90 mounted on bolts 88 forwardly of blocks 87.,

In the normal elevated position of the stripping mechanism illustrated in Fig. l, movable stripper heads 16, 17, 19, 2d are suspended in inclined positions such that the inboard beveled edges 51 and 66 of stripper shoes 16, 2t and 17, 19 are separated from the vertical edges of the adjacent shoes by distances greater than the width of core bars 40, '41, 42, 43. Consequently, when the (stripping mechanism is lowered into the mold, the separated stripper shoes may pass freely around the core bars and the latter may be received in the spaces between the fixed and movable stripper heads above the stripper shoes, whichv spaces are, of course, wider than the core bars even when the movable stripper heads have been moved to vertical, closed positions in the manner next to be described.

Movable stripper heads 16, 20 are automatically oscillated about the axes of supporting spindles 52, so as to move the stripper shoes 21, 25 toward closed positions, by a structurally simple arrangement of cam members which are mounted on the mold box and so disposed as to be contacted by stripper heads 16, 20 as the stripping mechanism is lowered into the mold and to positively move said heads about their pivotal axes in directions such as to bring stripper shoes 21, 25 into engagement with the adjacent shoes 22, 24 of movable heads 17, 19 just as downward movement of the stripping mechanism brings the stripper shoes into the plane of the lower edges of core bars 40, 43.

In the embodiment illustrated in Figs. 1, 2 and 3, the camming means comprises a pair of cam bars 91, 92 mounted on the upper surfaces of end liners 32, 33 of the mold box and each having a cam surface 93 which is inclined downwardly to meet the upper edge of the inner surface of the associated end liner. Cam bars 91, 92 may be removably fixed to the mold box in any suitable manner, such as that disclosed in my prior application Serial No. 451,477, or (if desired, can be formed integrally with end liners 32, 33.

7 As indicated in Fig. 1, cam surfaces 93 of the cam bars have their lower edges coplanar with the vertical surfaces of end liners 32, 33 defining the ends of the block forming compartments of the mold, and are so inclined and of such extent that, when the stripping mechanism is lowered with the stripper heads in their normal separated positions, the outboard vertical edges of stripper shoes 21, 25 of movable stripper heads 16, 20 initially contact the cam surfaces slightly below the upper edges of the" latter. As the stripping mechanism continues its downward movement, sliding contact between the outboard edges of movable stripper shoes 21, 25 and the inclined cam surfaces 93 causes stripper heads 16, to' rotate a 'as heads 16, 20, so that the beveled inner edges 66 of stripper shoes 22, 24 move under the lower edges of core bars 41, t2 and engage the vertical edges of fixed stripper shoes 23.

.The shoe closing action of the cam members is indicated by the broken line showing in Fig. l of the lower ends of the stripper heads as they pass by the core bars 7 with the outboardedges of stripper shoes 21, 25 sliding downwardly along cam surfaces 93 of cam bars 91, '92. It will be. evident from this showing that, because the inner stripper heads 17 19 do not begin to move inwardly until the beveled edges 51 of shoes 21, 25 of outer heads 16, 20 have cleared the lower edges of core bars 40, 43, the inner pair of core bars 41, 42 should be so mounted or constructed that the beveled edges thereof are located in a plane below that of the corresponding edges of core bars 40, 43, so that there may be a scraping contact between said edges and the beveled portions 66 of stripper shoes 22, 24 which serves to keep the surfaces free of adhering aggregate that might adversely affect the molding operation.

When all of the stripper shoes have come into abutment with one another below the core bars, the bottoms of the shoes present a substantially continuous surface for contact with the upper surface of the moldable material in the mold box, so that when the stripper heads momentarily come to rest on top of the material, and the mold box is vibrated in known manner to compact the blocks, the stripper shoes engage substantially the entire area of the topof each block and are thereby ca pable of exerting a uniform leveling and compacting action, as illustrated in Fig. 3.

After the block forming operation is completed, the stripping mechanism resumes its downward movement and strips the finished blocks from the mold box simultaneously with downward movement of anvil bars 13 and lock supporting pallet 12. The stripping mechanism is then elevated to withdraw the stripper heads from the mold box and return them to the initial position of Fig.

' 1, during which movement the movable stripper heads return to their normal separated positions under the force of springs 76 and 89 as the outboard edges of stripper shoes 21, 25 slide upwardly along cam surfaces 93 and ultimately out of contact therewith.

The advantages of the improved stripping mechanism of the present invention in comparison with those heretofore embodied in block molding machines of the same general type, including those of my prior Patent No. 2,566,787 and application Serial No. 451,477, will be apparent from the foregoing description of the mechanism illustrated. It will be evident, however, that the invention is not limited to the specific structure shown in the accompanying drawings, but is capable of a variety of mechanical embodiments, and that various changes,

a which will now suggest themselves to those skilled in the art, may be made in the form, details in construction and arrangement of the parts without departing from the spirit of the invention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is: 3 1. In a-bl0ck molding machine of the type including aesaere a mold box containing cores supported by at least three core bars extending across the top of each compartment of the mold box, stripping mechanism for engaging the tops of the molded blocks and means for producing relative movement of the mold box and stripping mechanism in a vertical direction to remove the blocks from the box, an improved stripping mechanism comprising a plurality of stripper heads arranged in a line transverse to the directions of said core bars and adapted to receive the core bars therebetween during the relative vertical movement of the mold box and stripping mechanism, means for pivotally supporting at least two adjacent stripper heads at one end of said line for substantially horizontal movement in the same direction relatively to the core bars, and means positioned adjacent the path of relative movement of the mold box and stripping mechanism for engaging only that movable stripper head which is positioned at the end of said line and moving the latter in a substantially horizontal direction during the relative vertical movement of the mold box and stripping mechanism, said stripper head at the end of the line having a shoe at its lower end of such width that, upon movement of said end head, the shoe thereof passes beneath the core bar between said adjacent heads and extends beyond said core bar sufficiently to engage and move the adjacent head in the same direction as that in which said end head is moved,

2. In a block molding machine of the type including a mold box containing cores supported by at least three core bars extending across the top of each compartment of the mold box, stripping mechanism for engaging the tops of the molded blocks and means for producing relative movement of the mold box and stripping mechanism in a vertical direction to remove the blocks from the box, an improved stripping mechanism comprising a plurality of stripper heads arranged in a line transverse to the directions of said core bars and having shoes at their lower ends the adjacent edges of which shoes are normally separated from one another so as to pass on opposite sides of said core bars and to receive the core bars therebetween during the relative vertical movement of the mold box and stripping mechanism, means for supporting at least two adjacent stripper heads at one end of said line for pivotal movement in the same direction about substantially horizontal axes parallel to said core bars to bring the adjacent edges of said shoes into contact with one another below the lower edges of said core bars, and cam means mounted on said mold box for engaging only that movable stripper head which is positioned at the end of said line and moving the latter about said substantially horizontal axis during the relative vertical movement of the mold box and stripping mechanism, the shoe of said stripper head at the end of the line being of such width that, upon movement of said end head, the shoe thereof passes beneath the core bar between said adjacent heads and extends beyond said core bar sufliciently to engage the shoe and to move 10 the adjacent head in the same direction as that in which said end head is moved.

3. An improved stripping mechanism according to claim 2 wherein said cam means comprises a member extending parallel to said core bars and having an inclined surface adapted to be contacted by a portion of the movable stripper head at the end of said line.

4. In a machine for molding cored blocks, the combination of a mold having liner members forming the end walls of the mold and at least one division member perpendicular to said liner members dividing the mold into a plurality of block forming compartments, a plurality of vertically disposed stripper heads on each side of and arranged in a line parallel to said division member each of said stripper heads having a shoe at its lower end adapted to enter one of the mold compartments and to engage a portion of the area of the top of a molded block in said compartment, said stripper heads and mold being vertically movable relative to one another to bring the stripper heads into engagement with the blocks in said mold, at least three core bars extending across the top of each compartment of said mold perpendicular to said division member and supporting a plurality of cores within the mold, a stripper head supporting member positioned above said mold, means for connecting at least two adjacent stripper heads at each end of each line to said supporting member for pivotal movement in the same direction about horizontal axes parallel to said core bars, means normally maintaining the pivotally mounted stripper heads in inclined positions with their shoes ofiset horizontally from the core bars and the mold compartments into which they are adapted to enter, and cam members on the upper surfaces of said mold liner members for engaging only the outermost pivotally mounted stripper head at each end of each line and moving the latter about their horizontal axes during the relative vertical movement of said stripper heads and the mold, moving the shoes of said outermost heads into abutment with the shoes of the adjacent pivotally mounted heads beneath the intervening core bars and therafter moving all of said pivotally mounted heads into alignment with the mold compartments beneath the core bars.

5. A machine for molding cored blocks according to claim 4 wherein each line of stripper heads includes one head which is rigidly fixed to said supporting member and two pivotally supported heads on each side of said fixed head.

6. A machine for molding cored blocks according to claim 4 wherein the two core bars closest to the end walls of the mold have their lower edges positioned in a horizontal plane above that of the lower edges of the other core bars.

References Cited in the file of this patent UNITED STATES PATENTS 2,319,291 Besser May 18, 1943 2,566,787 Zevely Sept. 4, 1951 

